Goniatitidae is one of three families included in the

ammonoid Ammonoids are a group of extinct marine mollusc animals in the subclass Ammonoidea of the class Cephalopoda. These molluscs, commonly referred to as ammonites, are more closely related to living coleoids (i.e., octopuses, squid and cuttlefish) ...

cephalopod superfamily Goniatitoidea, known from the Lower Mississippian to the Upper

Permian The Permian ( ) is a geologic period and stratigraphic system which spans 47 million years from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.9 Mya. It is the last period of the Paleoz ...

. They have sutures that form 8 lobes and characteristically lack sculpture. The ventral lobe, as for the superfamily, is bifurcated.

References

* Miller, Furnish, and Schindewolf 1957. Paleozoic Ammonoidea; ''Treatise on Invertebrate Paleontology'', Part L Ammonoidea. Geologocial Society of America and Univ of Kansas Press.
Goniatitidae
Paleo db 9/07/13 Goniatitida families Goniatitoidea {{Goniatitida-stub